Question

calculate arithmetic mean from the following data .( using assume mean method) (x. less than 10 f. 5 / less than 20 f. 15 / less than 30. f. 55 / less than 40 f. 75 / less than 50. f 100 /
​

Answer 1

Explanation:

−56

The given equation is 5x2−4x+2+m(4x2−2x−1)=0

The standard quadratic equation is ax2+bx+c=0 

Let's write given equation in standard form

(5+4m)x2+(4+2m)x+(2−m)=0

Here, a=5+4m,b=4+2m,c=2−m.

∴(4+2m)2−4(5+4m)(2−m)=0

For roots to be equal  ⇒b2−4ac=0

⇒5m2+m−6=0

⇒(m−1)(5m+6)=0

∴m=1,−56